Implementation of carrier phase measurements in GPS software receivers

In GPS receivers, carrier phase measurements are more precise than those of code phase, but they cannot provide explicit pseudorange due to integer ambiguity. The combination of code and carrier phase measurements can improve the precision of the pseudorange and the positioning performance of the receivers. The implementation method of carrier phase measurements in GPS software receivers is presented in this paper. The performance of combination of code and carrier phase measurements is analyzed by processing the collected signals. Experiment results illustrate that the error of the pseudorange can be reduced to the magnitude of millimeter by smoothing the data of 50 seconds.